I dont think Govt of Abdullah Ahmad Badawi have a choice at all.
They have to let the marchers proceed, with minimal incident as possible.
Maybe the incident at Masjid Jamek was a test, and soon word from the top, ie PM is that 'Dont harm the marchers.'
( even though yesterday, Friday he day he would come down hard on the marchers.)
As I said in my posting yesterday, any bloodshed in that vicinity of Dataran Merdeka, Masjid India etc will remind the whole nation of Reformasi of 1998.
And this time, thanks to superb organisational skills and internet, all eyes are on Malaysia.
If there was bloodshed, this would confirm to the world, and the people of Malaysia that Malaysia is ruled by a dictator who masquerade in the name of democracy.
Tell us about 'free and fair' election in Pakistan a month or so back.
Well, that was just an example. Zimbabwe, Iraq during Saddam, Fiji...